---

The mating disruption technique has been widely used for the control of several lepidopteran pests. In the present study, we assessed the efficiency of two formulations of SPLAT Neo, a wax emulsion containing E-11-hexadecenol, with and without the insecticide cypermethrin, in affecting mating disruption of Neoleucinodes elegantalis (Guenée). We also determined the best phenological age or stage of the crop for the application of the pheromone formulation, based on its effectiveness in reducing injuries on tomato fruits. We performed two field trials. The first field trial had three treatments: (1) Areas treated once (30 days after transplanting seedlings) with SPLAT Neo (mating disruption, formulation without cypermethrin); (2) Areas treated once with SPLAT Cida Neo (attract and kill, formulation with cypermethrin), and (3) Control plots, i.e. areas treated with the growers’ pest management procedures, based on pre-scheduled calendar applications of conventional insecticides. The use of SPLAT Neo with and without cypermethrin resulted in a significant season-long reduction of the average number of N. elegantalis eggs throughout the tomato cycle, compared to the control. Areas that received two SPLAT Neo applications had a lower number of males captured by monitoring pheromone traps, a lower number of eggs laid in the field, and significantly lower levels of fruit injury at pre, first, and second tomato harvests. The crop subjected to a single SPLAT Neo application, however, experienced reduction in fruit injury only at the second harvest. Our data suggest that two SPLAT Neo applications promote efficient control of N. elegantalis, resulting in significant reduction of fruit damage in tomato.

---

A microtube emitter is a simple, low-cost emitter in which the length can be adjusted according to the distribution of pressures along an irrigation lateral line to deliver uniform discharge. To accurately design micro-irrigation systems using microtubes, it is necessary to use an equation that correlates hydraulic parameters, microtube characteristics, and fluid properties. Therefore, the objectives of this research were: (a) To develop an equation for design purposes using dimensional analysis by Buckingham’s Pi theorem to represent the hydraulic processes in a microtube emitter operating in the laminar flow regime and (b) To compare the accuracy of the developed model against models that are currently used for microtube sizing. The data required to develop and validate the model was obtained experimentally in the laboratory by evaluating three types of microtubes with nominal diameters of 0.7, 0.8 and 1.0 mm. A model using pressure head, microtube length, flow rate, internal diameter, gravitational acceleration, and water properties was proposed and validated. The model for estimating hydraulic parameters in microtube emitters also presented better performance than other models available in the literature. Finally, an application example was presented and an irrigation lateral line using microtubes as emitters was designed using the proposed model.